Abstract: A pressure regulated system for an irrigation system including a reservoir of irrigation fluid, a pump, catheters for providing access to and egress from the irrigation site and a pressure regulation circuit, all connected in series with one another. The pressure regulation circuit includes a flow restriction branch having a normally-open valve and a variable orifice, diaphragm-operated, restrictor and a pressure accumulation branch, having a check valve, accumulator, and a normally-closed valve. A conduit running from the pressure accumulation branch to the diaphragm controls the pressure regulator. The operator may raise the pressure by closing the normally-open valve to direct pump flow to the pressure accumulation branch and thereby restrict the orifice of the pressure regulator until the desired pressure has been reached, and then releases the valve to maintain that pressure.

Abstract: A sentinel system is provided for a transcutaneous nerve stimulation device in which a sentinel pulse of known characteristics is produced at the device output prior to the production of a stimulation pulse. The output response is measured during the time of sentinel pulse production, and a sentinel warning signal is produced if an undesired output response is measured to alert the user to a potentially hazardous condition.

Abstract: A surgical tool for intercepting laser energy after it has energized a target site but before it energizes adjacent tissue. The instrument includes substrate of material having a high thermal conductivity for transmitting laser energy away from the surgical site and a highly absorbent surface material for absorbing radiant energy at the wavelength of the incident laser.

Abstract: A trocar apparatus and method for introducing a drainage catheter into a drainage area of the body. The trocar includes a hollow cannula and a rod. The rod has a closed distal end and is longer than the cannula so that it can slide into the cannula and, when fully inserted, project a predetermined distance past the distal end of the cannula. The proximal ends of the cannula and the rod have respective supports which will contact one another to limit the forward motion of the rod into the cannula and an interfitting device cooperatively disposed on the supports to permit the user to hold the rod and the cannula in fixed relationship during insertion of the trocar. A catheter holder is placed on the cannula support. The projecting end of the rod is inserted into a drainage opening in the distal tip of the catheter, and a proximal portion of the catheter is held in the catheter holder, so that prior to insertion the catheter is aligned generally along the outside of the cannula.

Abstract: A cannula including a guide and a cam housing rotatably supported about the guide into which a trocar obtuator and an endoscopy instrument may be inserted. A tapered proximal surface of the guide and a cooperating pin on the instrument rotate the instrument into proper rotational alignment. An axial slot extending from the distal end of the taper and a cooperating axial slot in the cam housing are aligned so that as the pin continues to slide axially into the cannula, the pin will interfere with a cam surface projecting from the side of the cam housing wall to rotate the cam housing out of the way as the pin proceeds further down the slot until the pin drops behind the cam surface into a pin retaining area. Thus, the instrument may be easily slid into the cannula, and through the action of the cam housing and guide, is held in proper axial, rotational and sealing alignment.

Abstract: A mounting assembly for twin microscope housings to permit synchronized tilting of the microscopes including a central spindle whose outside surface is threaded to accommodate an annular collar whose inside surface has corresponding threads. A fixed bracket is mounted to the bottom of the spindle, and an adjustable bracket is mounted about the adjustable collar. A tilt bracket is pivotably mounted to the bottom bracket and slidably mounted to the adjustable bracket so that as the annular collar is rotated about the central spindle to raise and lower the adjustable bracket, the tilt bracket tilts with respect to the longitudinal axis of the spindle.

Abstract: A transformer circuit including a primary coil with first and second voltage divider segments arranged in phase with equal inductances and a plurality of taps on the second segment. A switch is used to selectably ground one of the taps for varying the voltage impressed on the second segment. The transformer also has a secondary coil including first and second voltage divider segments arranged 180.degree. out of phase and having equal inductance. The secondary coil is heavily insulated, and the primary and secondary coils are coupled together to provide an output equal to the sum of the voltages applied to the segments of the secondary coil so that the transformer output can be varied by switching from one tap to another of the second segment of the primary coil and that the secondary coil can be heavily insulated and isolated from ground.

Abstract: A solenoid driven magnification changer shaft for a microscope with positive index stops. The solenoid shaft that both translates and rotates when the solenoid is activated. A coupler couples the solenoid shaft to the magnification changer shaft so as to permit the coupler to rotate as a unit with the magnification changer shaft but at the same time to translate axially on the magnification changer shaft.The magnification changer shaft includes a slot extending axially from a point spaced from the end of the shaft and extending a predetermined distance. The coupler includes a recess for receiving the free end of the shaft and a transverse bore for receiving a pin which extends through the transverse bore and the slot in the magnification changer shaft.The coupler and the surrounding driver housing include cooperating index pins and a stop pin.

Abstract: A coaxially aligned transformer having a secondary coil wrapped with a high dielectric insulating material wrapped on a support member and slidably supported between a lock block and a support base to permit the transformer electrical parameters to be adjusted by sliding the transformer core. A primary coil is supported coaxially about the secondary coil. Both the primary and the secondary coil include voltage divider segments having equal inductance with the primary coil segments arranged in phase and the secondary coil segments arranged 180.degree. out of phase. The secondary coil is completely insulated and isolated from ground. The primary coil has a number of taps which are connected to the contacts of a multi-position switch so that the voltage in one of the segments of the primary coil may be varied so that the output of the transformer may be varied. This transformer provides a switchable primary circuit and a fully insulated secondary circuit.

Abstract: A quick-release ratcheting holder for a surgical retractor which includes a spring detent to keep the holder from coming off the ring member when the retractor is relaxed.

Abstract: A completely disposable, permanently assembled drill for perforating bone structures, which includes a generally annular drill body. A primary drill member is slidably and rotatably received in the distal end of the drill body. A driver is slidably and rotatably received in the proximal end of said drill body. A pin and slot-type spring biased clutch is disposed on the confronting surfaces of the drill member and driver. The pin of the clutch projects through the triangular openings and the sidewall of the drill body so as to limit the throw of the clutch and to link the drill body and drill member together. The interaction of the pin against the triangular side of the slot in the drill body produces a component of force which tends to urge the clutch apart. When the drill is placed against the bone structure with a force sufficient to overcome the spring bias, the clutch will engage and the driver and drill member and the drill body will rotate together.

Abstract: A multi-position ratchet mechanism for holding a surgical retractor blade which permits a retractor blade to be rotated into the wound and retracted at the same time to duplicate the natural "toe-in" method of retraction achieved with the hand. The ratchet mechanism includes a ratchet holder to which is pivotably attached a ratchet pivot housing. The retractor blade is mounted in an opening projecting through ratchet pivot housing and held in position by a retractor pawl attached to the ratchet pivot housing. The ratchet pivot housing also has a curved ratchet which depends into a cooperating slot in the ratchet holder and engages a pivot pawl rotatably mounted and spring biased into the ratchet slot. The holder includes a transverse slot which slides onto an oval ring which is mounted about the incision site.

Abstract: A quick-release ratcheting holder for a surgical retractor which includes a spring detent to keep the holder from coming off the ring member when the retractor is relaxed.

Abstract: A completely disposable, permanently assembled drill for perforating bone structures, which includes a generally annular drill body. A primary drill member is slidably and rotatably received in the distal end of the drill body. A driver is slidably and rotatably received in the proximal end of said drill body. A pin and slot-type spring biased clutch is disposed on the confronting surfaces of the drill member and driver. The pin of the clutch projects through the triangular openings and the sidewall of the drill body so as to limit the throw of the clutch and to link the drill body and drill member together. The interaction of the pin against the triangular side of the slot in the drill body produces a component of force which tends to urge the clutch apart. When the drill is placed against the bone structure with a force sufficient to overcome the spring bias, the clutch will engage and the driver and drill member and the drill body will rotate together.

Abstract: A biopsy specimen collector for use with a vacuum source includes a closed receptacle having an inlet opening and an outlet opening. The outlet opening is adapted to be connected to the vacuum source. A removable cover provides access into the interior of the receptacle. A fluid channel tube inside the receptacle has one end connected to the outlet opening, with its other end being open and being positioned substantially at the geometric centroid of the receptacle to facilitate operation of the collector without regard of its orientation during use.

Abstract: A surgical retractor assembly includes a support post having a lower portion and an upper portion, with the lower portion having an adjustable clamp for attaching the post to a rail provided on a surgical operating table. This clamp is capable of attachment to the rail over a flexible surgical drape. A screw mechanism is associated with the clamp so that the clamp can be attached and adjusted by the operator in an area above the rail on the surgical table. An extension rod is adjustably connected to the post and is adapted to extend in a direction generally over a patient on the operating table. A rigid ring member is connected to the extension rod for positioning a plurality of retractor blades for use on a patient. At least one retractor blade is mounted on the ring member.

Abstract: An improved battery charger of the type having a housing with a source of electrical energy therein suitable for recharging units capable of being electrically recharged. The housing includes a plurality of cavities each arranged to accommodate a unit to be recharged, and each cavity has electrical contacts which are positioned to contact the terminals of the unit inserted into each cavity for delivering electrical energy to that unit. The improvement comprises a switch in each cavity which is activatable by insertion of the unit therein, the switch being separate from and free from direct contact with the electrical contacts, but electrically connected to the energy source which, in turn, energizes the electrical contacts for recharging the unit upon activation of the switch.

Abstract: A quick connect-disconnect electrofluidic junction assembly for simultaneously transferring fluid and electrical energy from respective sources of supply. The assembly includes a female terminal with an internal receptacle one end of which is open and surrounded by a peripheral wall. An electrical contact is positioned inside the housing and spaced apart from the open end. A fluid passage extends through the housing and communicates with the receptacle. A male terminal includes a hollow connector body which is adapted to be push-fit into the receptacle through its open end, with an electrical contact on its forward end adapted to mate with the electrical contact in the housing. A sealing element is located around the periphery of the body for providing a fluid-tight seal between the body and the interior wall of the housing when inserted therein.

Abstract: Method for fixation of prostheses to bone with sterile non toxic polymers such as polycaprolactone which are formable viscous liquids or putty-like solids at temperatures within the range of 45.degree.-75.degree. C. and hard, rigid solids at temperatures below about 42.degree. C., and to a sterile package containing such polymers.